The Vigilante
by Spunky0ne
Summary: Tetsuya Kuchiki is abducted and subjected to an illegal lab experiment under the direction of Mayuri Kurotsuchi. When the test goes wrong, Tetsuya's fate is unexpectedly bound to that of one of the Seireitei's most vile criminal's. But...fate has more in store for them than Sousuke Aizen can even imagine! Aizen/Tetsuya, Bya/Ren, Urahara/Ichigo...mpreg


**The Vigilante**

**(Apologies for not being able to post as much Aizen as I wanted to, but Aizenfans, don't worry! I will work very hard to get lots of Aizen to you this last week of Aizenmonth, and if necessary will spill over into June! And I won't forget our fave bad boy after that either. Enjoy the new story! I am off to finish the next chapter of On Top and some other Aizengoodies too! Aizenlove to all!)**

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**Chapter 1: Disruption**

"Did you bring him?" Captain Mayuri Kurotsuchi asked the dark, cloaked figure who approached where he waited in the darkened laboratory, "I went to a lot of trouble and spared no expense to identify him, so you had better not have damaged him!"

"He is not damaged," said the cloaked man in a low, rasping voice, dropping the bound, hooded and gagged shinigami he carried roughly onto the floor at the twelfth division captain's feet.

The shinigami made an exclamation of pain as his body struck the floor, and beneath the gag, he struggled to speak.

"He is, however, understandably angry at being abducted," the cloaked man went on, "But I explained that he is needed for a good cause."

"Of course," Mayuri said silkenly, "Protecting Soul Society from the wrath of the quincies is important. But it seems that everyone has forgotten that we have another threat in our midst...one that needs to be eliminated. I would, of course, go through the proper channels if the Seireitei wasn't in a shambles and all of us under martial law. But with the way things are, we can hardly call a council meeting to discuss such a trifling thing as what should happen to that bastard, Sousuke Aizen. And we can't take the chance that he will join with the enemy forces. Besides," he said, grinning maniacally, "the scientific properties of what I am doing are _amazing_! Kisuke Urahara never dreamed of something like this. And when Aizen dies and everyone knows how he died and who it was who killed him, I will be respected as the most brilliant scientist in the three worlds!"

"I am so glad that you are pleased," the thug said dryly, "Now, you promised me..."

"Yes, yes, of course," Kurotsuchi muttered, rolling his eyes, "Take the money and begone, fool. Go. And remember not to breathe a _word_ of this to anyone."

He waited, smirking as the cloaked man accepted the bag of money from his hand and started towards the door. Halfway there, he made a sound of distress, and slowly collapsed onto the floor. Mayuri approached him in slow, measured steps, listening to him gurgle and gasp for breathe.

"Or," he said in a low, wicked tone, "Just don't breathe. It's all the same to me. Thank you for your services. I do appreciate your help, but unfortunately, with you having too much information, I cannot let you live."

The collapsed man's body convulsed sharply, and he made a last gasping cry of distress as the poison in his system overwhelmed him and he fell still. A moment later, his body disintegrated and disappeared in a cloud of green smoke.

"Ah," Kurotsuchi said, turning back to observe the bound shinigami, "Now, as for you, listen carefully. You are, as of this moment, a new test subject in a very special study. Before we begin, why don't you just confirm who you are. I don't want there to be any mistakes."

He slipped the gag out of the shinigami's mouth and pulled the hood back to reveal a lovely, youthful, male face with pale skin, wide sapphire eyes and raven black hair that tumbled loosely around his face and shoulders. The man scowled and Kurotsuchi smiled down at him.

"You!" the shinigami gasped, "Why are you doing this? How dare you, a captain? You are supposed to protect justice in Soul Society, not tread upon it! Let me go, you bastard!"

"Oh, stop your struggling, little noble. Yes, I know you are a Kuchiki. Tetsuya Kuchiki, ne?"

He laughed softly at the defiant glare Tetsuya gave in answer.

"Well then, of course you are Tetsuya Kuchiki. And, given that compound I had him give you, your stallion...Arashi, is it? He should have merged with you."

"He is not supposed to be merged with me except in my inner world or in the spirit dimension!" Tetsuya snapped viciously, "My body cannot tolerate the combined power! That is why we are two in Soul Society! But you know that, don't you? You were given full information about my powers when I reached bankai!"

"Yes, I was," Kurotsuchi announced, looking pleased with himself, "I am most responsible for knowing about all powerful shinigamis so that those who _go rogue_, as it were, can be contained, if necessary. It is an important task, given the history of people like Sousuke Aizen, you know. But, back to the test. Do not worry about your pretty little body, Tetsuya Kuchiki. You will not destabilize here. I have seen to that. It is just that, for this test, I need you at full power. And I am going to raise that power a bit more."

"What?" Tetsuya breathed, alarm plain in his fine features, "You cannot...!"

"Of course I can," the twelfth division captain laughed, "Come now, Nemu! Get this boy up off the floor and put him over there on the examination table."

"Yes, Master Mayuri," the man's vice captain said quietly.

Tetsuya struggled as he was lifted, but was unable to break free of the lady officers inhumanly strong grasp.

"Put me down! Let me go at once!" Tetsuya objected, "What are going to do?"

Mayuri watched with glinting eyes as Nemu quickly laid Tetsuya on the examination table and set him in restraints.

"Hurry, you stupid girl," he said impatiently, slipping an extra pair of latex gloves onto his hands, "We don't have forever, you know. You never know when that insipid, drunken fool head captain of ours will call a meeting or some of those pesky quincies will attempt to break in here again."

"I am sorry for my slowness, Master Mayuri," the girl apologized, "I will attempt to do better."

"Just get him tied down," the captain said off-handedly, "We need to get started immediately!"

"Yes, Master Mayuri."

Tetsuya cringed as the twelfth division captain leaned over him and laid his hands on the noble's chest, locating his spirit centers and placing electrodes over each of them.

"Nemu, inject that stabilizing compound now."

"What? What are you doing?" Tetsuya cried, "Stop! Stop, please!"

He struggled more fitfully as a needle bit into his arm.

"What is that? What are you...?"

"Give him the sedative now."

"No! Stop!"

Tetsuya's eyes slowly glazed over as the medication worked its way into his system. His body went limp under Kurotsuchi's hands, making the captain smirk as he went on with his work.

"Infuse him with the additional power now," he ordered his vice captain, "Go slowly or his spirit centers will explode like the last one's did and we will have another horrid mess on our hands. I doubt we'd get away with another of you doltish explanations."

"I will be careful," the girl promised, beginning the infusion.

The two watched the monitors around the now unconscious noble as the infused power entered his spirit centers. One of the machines beeped ominously, and even sedated, Tetsuya moved sluggishly in protest.

"Go more slowly even, you fool!" Kurotsuchi said hotly.

"I will."

Tetsuya slowly quieted and the complaining monitor fell still as the infused power filled the young man's body, making it glow very softly. Mayuri made a pleased exclamation as he scanned the readouts that poured out of the machines around Tetsuya.

"Excellent! Excellent! He is handling the additional power flawlessly! Nemu, wake him now. Then, go and bring our friend Aizen."

He gave a cackling laugh as the girl reduced the flow of medication into Tetsuya's system, then started for the door.

"Such a lucky turn that when the prisons were breached in the last attack, it was decided that our division was best equipped to contain that man."

He looked down at Tetsuya as the young man came awake, his blue eyes wide with terror and his mouth opening into a desperate scream.

"Wha-what did you do?" he cried, turning his head to one side, then the other, and looking down at his glowing body, "You monster! How can you do something like this and still call yourself a captain?"

"I am a research scientist," Mayuri said calmly, "That is my first occupation. I work for the benefit of the Gotei 13 as one of their captains. And that is what i am doing now."

"But you cannot just _harvest_ people at will! You cannot use people who haven't given their consent!"

"Listen to you go on and on. You haven't even heard about what I am doing."

"Well, you hadn't exactly offered the information," Tetsuya hissed, "So, if I am serving the needs of the Gotei 13, what exactly am I doing that is so important?"

"What's so important? What's so important, he asks!" Mayuri repeated mockingly, "What, my young friend, could _be_ more important than _putting an end to Sousuke Aizen and his evil_!"

"You are going to k-kill Sousuke Aizen?" Tetsuya asked, his heart pounding, "How?"

"You know, I suffered with that question...just _agonized_ over it, ever since we found out that the bastard had made himself immortal. The catch that I found is...that he is only immortal until the hougyoku is somehow separated from his body. But, how to do that! I had to give it months and months...over a year of hard thought and went through many failed tests before I realized. You see, even the most _fused_ things are still existing in separate molecules. And if something could convince the hougyoku that it could be separated from this man that it had rejected, then I could separate them and kill Sousuke Aizen, once and for all!"

"B-but...the sheer number of molecules," Tetsuya said frantically, "How could you possibly..."

"Oh, it wasn't easy. I reasoned early on that an aqueous solution and a shock of some kind was needed to destabilize his body and throw the molecules into chaos. But, the hougyoku would not cooperate when I tried to use water. It assisted me in learning that only a water wielding shinigami...a very powerful one could provide the aqueous solution for the task. You see, when you reached bankai and your file was forwarded to my division, I discovered that you weren't just powerful, but were being trained for a post in the king's Norite, his mounted guard. Oh, you haven't transcended yet, which is why your Arashi resides outside your body...so that you can handle the power that belongs to you. You won't be able to wield that full power until you are called to join the king in the spirit dimension. But, I posited that if I stabilized your body in the lab, and then boosted your power, you would be a balance for Sousuke Aizen's power. That means, you would be perfect to provide the aqueous solution for the explosion and rearrangement of particles. When the test is done, the hougyoku will be separated from Aizen, and we will be free to kill him, as he deserves."

"And what about me?" Tetsuya asked, his voice shaking slightly, "What happens to me?"

"Well," the captain said, looking into Tetsuya's frightened eyes, "Unfortunately, as you probably know if you've studied any chemistry at all, the heat generated by the reactive exchange will turn the water to steam and it will evaporate. You, my friend, will die. But, think of what you will be doing for Soul Society! I read in your profile that you are very devoted to the protection of your leader. And remember what the quincies did to him? Imagine what would happen to him if the quincies learned Aizen was here...and they came and took him and got him on their side. This, my young friend, is why I had to cut some corners to save time and keep this secret. If we are to end Aizen's life, then we must do so before anyone can come and stop us. Now...what do you say? Are you willing to die to save Byakuya and the Seireitei? On second thought, don't answer. Because it doesn't matter what you say. Sousuke Aizen must die, and for that to happen, you must be sacrificed. A small enough cost, to my thinking...one young shinigami to save the three worlds. That's not a bad exchange, ne?"

He risked a look at the shinigami's face, expecting more anger, more argument. But Tetsuya's sapphire eyes had taken on a worn, defeated look, and his body relaxed within the restraints.

"What am I to do?" he said in a soft, strained voice that was barely above a whisper, "Do you even know that this will work? You said that there were failures before."

"I have worked out the problems," Mayuri said dismissively, "Make no mistake. You are the answer to getting the hougyoku separated from that man and allowing us to kill him."

"Without a trial? Without the blessing of Central 46? Without orders from your captain commander?" Tetsuya inquired softly, "Tell me, Mayuri Kurotsuchi, when did we become a group of amoral vigilantes?"

"What did you say? You impertinent little..."

"As much as there is need for Aizen to pay for his sin, it needs to be done honorably. If you will only notify the Gotei 13 and Central 46, and let them order Aizen's immediate execution, I will willingly sacrifice myself."

"You don't..."

Mayuri froze.

"What?" he asked, blinking.

"I said," Tetsuya answered, "If you will gain the proper permissions, then I will volunteer myself to be sacrificed to end Sousuke Aizen's life."

_He must know that the military and Central 46 councils would never allow this kind of an experiment. That must be why he is demanding it._

_Or could it be?_

_Could he really be that selfless?_

_What a fool..._

"I am sorry," Mayuri said, looking down into Tetsuya's dark, sad eyes and speaking with unusual sincerity, "I think that you and I both know what they would say to that."

"May I at least speak to my cousin before...?" Tetsuya pleaded softly.

"And what would you say?" the captain asked, shaking his head, then looking up as Nemu entered the room, wheeling in Aizen, who was carefully bound to another examination table, "I can't offer you any reassurances. But...I will make your end painless. I will let you sleep through it, if you wish. You do not need to suffer, seeing death approach."

Tetsuya sighed and turned his head slightly, meeting Aizen's curious eyes as the twelfth division captain set about working with the machines around the two. He couldn't think of anything to say, so he waited for Aizen to speak.

"Why are you here?" he asked softly, when their captors were turned away, "What are those two plotting?"

"What do you think they are plotting?" Tetsuya replied softly, "They want what we all do. They want you to die."

"Is that so?" Aizen said, looking amused, "You must crave my death very badly...on a personal level, if you have made yourself vulnerable to him. You are a noble, no?"

"I am."

"And your name, if you don't mind sharing?"

"Tetsuya. I am Tetsuya Kuchiki."

"A Kuchiki," Aizen repeated appreciatively, "So, he needed someone with some respectable power...and not an officer of the Gotei 13? Unless perhaps, you joined after I left?"

"No. I am not in the military."

"But you are powerful," Aizen stated firmly, "I can feel it. Do you have a bankai?"

"Yes."

"I see. And what is your power, Tetsuya Kuchiki?"

"I am a water wielder," Tetsuya explained, "I conjure waterforms, which I use to conceal myself during battle. They are useful for positioning myself for attack, or for escaping attacks by my enemy."

"And your bankai?"

"My zanpakutou's true form is a cyclone of water that ensnares the enemy and sweeps him away. The water can also freeze and be expelled as ice blades."

"Hmmm. you are powerful. I give you that. So, why are you here? I am sure that you know this fool is probably going to kill you, ne? Do you want that badly to die, Tetsuya?"

"No. I don't want to die at all. But...as you see, I have no choice. He had me abducted, and has carefully bound me so that I cannot use my powers to escape."

"Well, that would seem to be a rather large problem, Tetsuya Kuchiki," Aizen said smoothly, "But if you really don't want to die, I could tell you how to save yourself."

"But you want me to help you escape. Is that it?" Tetsuya asked, frowning, "Rest assured, I would rather die a worse death than this, rather than see you walk free again."

"Ah...well. I had to try," Aizen said, his calm tone setting off warning bells in Tetsuya's head.

But he was unable to think further on the matter as Mayuri returned to them and glared down at the two.

"Any last words?" he asked them.

"Will you unbind my hand?" Aizen asked, "The young man does not want to enter death alone. And as you plan to kill us both, you could certainly spare the kindness."

"What do I care?" Mayuri said off-handedly, uncovering just Aizen's fingers, "Hold hands all you want. You are going to die, Sousuke Aizen. And I can promise you, no one will mourn you. Not even that insipid little mouse in your old squad. We have deprogrammed her. You are truly alone now, with a world that hates you."

"But, you know what that is like, don't you, Mayuri Kurotsuchi?" Aizen asked sedately.

The twelfth division captain scowled.

"Enough! Nemu, it is time! Prepare the disruptor!"

Tetsuya's heart pounded and he felt tears in his eyes, but he forced himself to remain silent as the disruptor was brought to bear on the two of them. He flinched as he felt Aizen's fingers touch his, then caught his breath as he heard Aizen's voice in his mind.

"_Be calm, Tetsuya Kuchiki, we will not die. The hougyoku may not be responding to me anymore, but it still can respond to the call of the hearts of those around it. You want to live. You want to escape this man. Trust the hougyoku...and that will happen_."

Aizen's voice disappeared as the roar of the beam firing from the disruptor sounded, but Tetsuya was stunned at feeling no pain, no sign that he had died, and at hearing another, softer voice in his mind.

_Think of a familiar body of water...one you know very well. Picture it in your mind._

Instantly, Tetsuya recalled the lake and waterfall at Kuchiki Manor.

_Now, open your heart to me and let me save you._

The rushing grew louder in Tetsuya's ears and fear seemed to swallow him whole. He took a breath to scream, but found suddenly that he was underwater. He breathed easily, trusting his innate ability, which allowed him to survive in water. Realizing that his hands and arms seemed to be free, he kicked his legs and surfaced, then swam to the shore, where he dragged himself out of the water, and collapsed, unable to move anymore. He laid on his belly, panting and coughing out water.

Then, he heard someone else doing the same beside him. He turned his head and found himself looking at Aizen's smiling face.

"Thank you, Tetsuya," he said gratefully, "The hougyoku was able to use your powers to move us from the lab to this lake. And, if I am lucky, that fool will think we were just incinerated by his ridiculous toy disruptor."

Tetsuya stared at the other man, unsure what to say. His eyes rounded and he struggled onto his knees, backing away as Aizen started towards him.

"However," the former captain went on in that same, dead-calm voice, "If you reappear, then he will know I have escaped."

Tetsuya dragged himself onto his feet and started to run, only to double over, screaming, a moment later.

"What is this?" Aizen mused, pausing and watching raptly as Tetsuya's body shimmered for a moment, then a large, black equine form erupted out of him and collapsed on the grass at the edge of the water.

"Arashi!" Tetsuya sobbed, dropping to his knees and reeling as he began to lose consciousness.

Aizen looked up as he heard approaching voices sound on the cliff above them.

_"Hougyoku, if we are seen..."_

_"Do not be concerned. Open the doorway."_

Aizen's eyes widened as the collapsed stallion opened his glazed eyes and climbed to his feet. Tetsuya, too, stood and climbed quietly onto Arashi's back, then waited wordlessly.

"_I meant to kill him. He could give me away."_

_"He is too weak to fight us right now," _the hougyoku assured him, _"And when we arrive in the living world, you know where to find restrictive gigais for them."_

_"Ah yes, Kisuke Urahara's shop."_

_"Yes."_

_"Then, let us go," _Aizen said, climbing onto Arashi's back and wrapping his arms around Tetsuya's slim waist.

Arashi stepped forward, oblivious as the doorway opened into the precipice world. The doorway closed again behind them, leaving the two Kuchiki house guards who had arrived, looking about blankly.

"What was that?" one said to the other.

"I don't know, but there's nothing here now. Come on, let's go make a report."


End file.
